Electric switch



Aug. 11, 1926.

A. E. BLACKMAN tnecwnlc SWITCH Filed Jan.- 16, 1922 2 Sheets-Sheet 1 $1 -1- W gfWTOR My Aug. 17 1926. 1,596,794

A. E. BLACKMAN ELECTRIC SWITCH Filed Jan. 16. 1922 2 Sheets-Sheet 2 IIIIIIIII IIIIIIIJJ 11 :11 111111111 I!!! [fill] 11 7 I 111 IL Patented Aug. 17, 1926.

UNITED STATES ALBERT E. BLACKMAN, OF MOUNT VERNON, NEW YORK.

ELECTRIC SWITCH.

Application filed January 16, 1.922.

This invention relates to electrical switches and more especially to that class of electric switches adapted for starting motors and comprehends fused and unfused line terminals. To obviate the blowing of the fuses which would occur if the load were suddenly thrown on the fused line terminals, positive means are rovided for compelling the switch to be t rown on the unfused terminals prior contact with the fused line terminals.

The described features of my invention are shown in the accompanying drawings as adapted to a switch mounted in the conventional iron-clad casing and likereference characters are applied to the corresponding parts in the several views.

Fig. 1 is, a front view of a three-pole doub e-th'row switch mounted Within an iron casing wherein my improvements are incorporated, the cover of the case being shown open in this view, and the switch retained in a neutral position, some parts being shown in section.

Fig. 2 is an enlarged sectional view taken on the plane of the line A--A in Fig. 1, showing the switch operating mechanism restrained in the intermediate or neutral position, certain parts being broken away.

Fig. 3 is a similar View as that shown in Fig. 2 showing the switch crating means moved to the, unfused end'o the switch.

Fig. 4 is a side elevation from the left of Fig. 1 part of the casing walls being broken away and showing the switch and operating means moved to the fused line terminal.

Fi 5 is a plan view of a switch operating mem'er.

Fig. 6 is a side view of the same.

The switch contact elements illustrated are of typical construction embodying a series of three double armed'switch blades 7 pivoted at 8 on the terminal 9 mounted on the switch base '10,. these switch blades are adapted when rocked on their pivot to engage with the terminals 11, which have no fuses in their line and when rocked in the reverse direction toengage with the termnals 12 which, have the fuses 13 held inline as will be readily understood.

The switch contact elements are shown as secured in thecasing 14. by the. screws 15 passed through the switch base 10 intoengagement withthe near wall of the casing.

Serial No. 529,477.

The operating means for the switch is shown 1n the form of a manually operable handle 16 cooperating with ahub portion 17 pivotally mounted in the wall of the casing and which engages with and carries a yoke shaped rod 18, part of which engages the claws or uprights 19 secured to a crossbar 20 which rocks the several switch blades, thus providin means for operating the switch blades t rough the handle 16.

The rod 18 supports centrally and is acted upon by a spring 21 having spaced arms 22 and 23, one of them bearing a ainst. a fixed abutment, such as the rear wa l of the easing and the other bearing against an offset portion of the rod 18. The spring 21 is adapted to rotate the switch mechanism and close the circuit at the fused terminals.

Mounted upon the hub 17 of the operating handle is adisc 24, which is preferably formed of sheet metal and which possesses elements or surfaces adapted to co-act with a pawl 25 in regulating the operation of the switch.

The disc 24 is provided with an upstanding portion 26 formed to engage with the rod 18 and is rotated therewith.

Another portion 27 of this disc is ada ted to form a track against which the paw 25 .may bear, this portion is notched to form an abutting shoulder 28, adapted to co-act with the pawl in restraining the switch and its operating mechanism in aneutral osition. A side of the disc is also provi, ed with two elevated lugs 29 and 30 adapted to cooperate with the. pawlv 25 in operating the switch.

The disc is shown formed with a central boss 31' designed to elevate it from the easing wall and adapt it to this formof construction.

A washer may be placed on the hub 17 between the engaging rod 18 and the disc 24: to hold the latter in position against the wall of the casing.

Adjacent to the disc 24 the pawl 25 is mounted upon apivot 33 erected on a plate 34 which is provided with. a bracket 35 to which may be secured a flat spring 36. This spring is adapted to press through a bracket 37 formed on the pawl 25 against its pivot 33, thus when. the bracket 37 is moved on its pivot to either side of the line, of thrust. the pressure of the spring will tend to rotate the pawl in the samedirection.

The pawl 25 is formed with a linger 38 projecting within the track of the lugs 28 and 29, and is adapted to engage with and be rotated by them in reverse directions.

The pawl is also provided with an arm 39 adapted to limit its range of movement by striking the bracket 35 or a stop d0 erected on the plate 34.

To operate the switch, assuming that the several parts are positioned shown in l and 2, the switch operating parts so restrained by the pawl engagincthe shoulder 28, the operating handle ma; be. moved only to bring the switch lcni cs in contact with the untu ed line l1. sinuiltaiwousl v with the comthis action, the lug ill) on the disc adapted to engage with and rotate, th linger 88 witn the pawl 25 and its bracket 3 on their pivot 33, thus littingr the pawl tn the disc and turning the bracket to a p sition shown in 3 where it may be retained by the spring 36.

The switch operating mechanism with the switch liHlVQS 7 when released from this position by the operator is adapted to be automaticall rotated by the spring 21 to the fused end of the switch thereby breaking contact oi the switch knives with the terminal 11 and forming contact with the tused line terminal 1?, simultaneously with this action the lug 29 is adapted to engage with and rotate the finger 38 vith the pawl to a. position substantially as shown in Fig. 4:. The pawl in this position is held under the tension of the spring 36 on the bracket 37 against the track 27 of the disc as illustrated in Fig. 4.

The switch through its operating handle 16 may now be moved to its neutral position which point the pawl being under tension 01" the spring will engage with the shoulder 28 and there retain the switch, thus completing a cycle of operation.

I have described and illustrated these embodiments or" my invention as adapted to a casing. but it is obvious that these improvements in switches are notdependent on their housing and may be employed in other forms and I do not limit myself solely to such applications as are herein shown, for it is intended that all matter herein contained shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A device of the character described comprising two sets of stationary contacts, switch blades adapted to control the current through said contacts, switch operating means for rotating the blades into position to close the circuit through one set of contacts and into another position to close the circuit through the other set of contacts. a disc fixed to said switch operating means and rotating therewith, said disc havo a plurality of lugs, a pawl having a pluraiitv at l! adapted to be shifted into different positions by said lugs whereby the sequence oi operation of the switch operating means is controlled by said pawl.

2. A device of the character described comprising two sets of stationar contacts, switch bhides adapted to control the current through said contacts, switch operating means for rotating the blades into position to close the circuit through one set of contacts and into another position to close the circuit through the second set ot contacts, a substantially disc shaped member fixed to said switch operating means and rotating tl erewith, said member having a plurality of dilierenth positioned surfaces, pawl adapted to be shifted into ditlerent positions by surfaces of the disc, one surface of the disc being adapted to lock with said pawl when the operating mechanism is in neutral position to prevent closing the circuit through the second set of contacts, another ot said surfaces being adapted to shift the pawl clear of said first surface when the circuit is closed through the first set of contacts and still another surface bee inc; adapted to turn the pawl into position for locking with said first surface when the switch operating mechanism moved into neutral position from closing the circuit through the second set of contacts.

A device of the character described comprising two sets of stationary contacts, switch blades adapted to control the current through said contacts, switch operating means for rotating the blades into various positions, a pawl adapted to coope ate with the switch operating means for controlling the sequence of operation of said operating means, said pawl having a plurality of dill'erently positioned surfaces and a plate spring adapted to successively engage said surfaces for retaining said pawl in a plurality of positions.

t. A. device of the combining two sets of stationary contacts, a switch blade, a shaft to move the switch blade, a notched dis: secured to the shaft, having an outstanding lug, a trip element adapted to cooperate with the disk and means to hold the trip element in difi crent positions, the trip element being shifted to dilterent positions by the coaction of the lug with the trip element.

A device of the character described comprising two sets of stationary contacts, switch blades adapted to control the current through said contacts, switch operating means for rotating the blades into various positions, a member operatively connected to said switch operating means and rotating in fixed relation thereto, said member having a plurality of differently positioned surfaces, a pawl adapted successively to encharacter described gage with said surfaces for controlling the sequence of operation of said operating means, said pawl having a plurality of different-ly positioned surfaces and spring actuated means adapted successively to engage said surfaces of the pawl for retaining said pawl in a plurality of positions.

6. A device of the character described comprising two sets of stationary contacts, switch blades adapted to control the current through said contacts, switch operating means for rotating the blades into various positions, a pawl adapted to cooperate with the switch operating means for controlling the sequence of operation of said operating means, said pawl having a pluralit of projections, one of said projections, a apted to prevent the closing of the circuit through one set of said contacts from the neutral osition of said blades, another of said proections adapted to be engaged on one side by the switch operatin means for shifting said pawl so that said first projection is clear of said operating means when said blades are moved to close the circuit through the second set of contacts, said switch operating means being adapted to engage the other side of said second projection, as said blades are moved to close the circuit through the former set of contacts, for shifting said pawl again into position to prevent the closmg of the circuit throu h said former set of contacts when the blades are moved back to neutral position.

7. A device of the character described comprising two sets of stationary contacts, switch blades adapted to control the current through said contacts, switch operating means for rotating the blades into various positions, a sheet metal disc fixed to said operating means for rotating therewith a pawl adapted to cooperate with said disc for controlling the sequence of operation of the switch operating means, said disc having a notch in its edge for engaging with said pawl to prevent operation of the switch blades from neutral position to closing the circuit through one set of contacts, said disc also having a plurality of projections from a side face adapted to engage with the pawl, whereby said pawl is moved from said notch as the blades are moved into contact with the second set of contacts and moved again into position for engaging with the notch when said blades are moved into contact with the former set of contacts.

8. Releasing means for switch mechanism comprising a rotatably mounted pawl having its edge divided up into a plurality of plane surfaces making substantial angles with each other and a plate spring adapted to ride over said surfaces for retaining said pawl in a plurality of positions.

9. Releasing means for switch mechanism comprising a rotatably mounted pawl having a plurality of differently positioned surfaces and spring actuated means adapted to ride over said surfaces, said pawl being retained in successive positions corresponding to said surfaces by the pressure of said spring actuated means successively upon said surfaces.

10. In releasing means for switch mechanism as claimed in claim 9, a disc adapted to rotate in fixed relation to said mechanism, said disc having a plurality of distinctly defined surfaces adapted to engage with the pawl for controlling the sequence of operation of the switch mechanism.

11. Releasing means for switch mechanism comprising a rotatably mounted pawl having a plurality of differently positioned lugs and spring actuated means adapted to ride over said lugs, said pawl being retained in successive positions corresponding to said lugs by the pressure of said spring actuated means successively upon said lugs.

12. A device of the character described comprising two sets of stationary contacts, switch blades adapted to control the current through said contacts, switch operating means for rotating the blades into position to close the circuit through one set of contacts and into another position to close the circuit through the other set of contacts, a disc rotating in fixed relation to said switch operating means, a pawl having a plurality of legs, said disc being adapted to co-operate with one of the legs of said pawl for shifting said pawl into different positions whereby the sequence of operation of the switch operating means is controlled by said pawl, and spring actuated means adapted to slide against another leg of the pawl for retaining said pawl in its various positions.

In testimony whereof, I subscribe my name to the foregoing.

ALBERT E. BLACKMAN. 

